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System Analysis Method Based On Simulation Big Data, Guangya Si, Wang Fei, Liu Yang Nov 2019

System Analysis Method Based On Simulation Big Data, Guangya Si, Wang Fei, Liu Yang

Journal of System Simulation

Abstract: Wargaming and exploratory simulation with large-scale simulation systems produce massive simulation data. These data contain many complexity patterns of war, and are significant samples for studying the mechanism of war. Based on the definition of simulation big data, an analysis framework based on simulation big data is proposed, which is divided into three levels: simulation environment and data planning, big data acquisition and storage, and analysis and mining. The simulation data planning and analysis and mining are briefly introduced.


Optimal Compensation Control Strategy For Four-Axle Vehicle With All-Wheel Steering System, Baohua Wang, Yu Chao Nov 2019

Optimal Compensation Control Strategy For Four-Axle Vehicle With All-Wheel Steering System, Baohua Wang, Yu Chao

Journal of System Simulation

Abstract: Aiming at the problem of poor stability of traditional multi-axle commercial vehicles, an optimal control strategy for multi-axle steering wheel is proposed. Through the establishment of the four-axis vehicle model, the wheel angle proportional feed-forward control algorithm and the yaw rate feedback control algorithm are studied. The optimal compensating control algorithm of the wheel angle proportional feed-forward and yaw rate feedback is proposed, and the control strategy is also verified through joint simulation. The results show that the full-wheel steering optimal compensation control strategy can keep the center-of-mass skew angle close to zero at all vehicle speeds, …


Semantic Value-Driven 3d Upright Posture Figure Model Transformation, Yangfu Ren, Yuanyuan Pu, Xu Dan, Wenhua Qian Nov 2019

Semantic Value-Driven 3d Upright Posture Figure Model Transformation, Yangfu Ren, Yuanyuan Pu, Xu Dan, Wenhua Qian

Journal of System Simulation

Abstract: In medical equipment, clothing design, film production and computer games, 3D human body model is an indispensable element, but directly obtaining it by means of scanning the human body model does not directly apply in many environments, so we need to moderate deformation model according to the environment. The operation difficulty of the model of deformation is considered, and the deformation effect is achieved. For studying the 3D human body model deformation problem, the deformation of semantic driven model is introduced. Semantic values of height, leg length and shoulder height were obtained by measuring the position of joint points …


Dynamic Interference Detection Algorithm For Bearing With Scar, Jinyuan Jia, Naihao Zheng Nov 2019

Dynamic Interference Detection Algorithm For Bearing With Scar, Jinyuan Jia, Naihao Zheng

Journal of System Simulation

Abstract: To solve the dynamic interference detection problem of scar bearing in visual assembly, an efficient dynamic interference inspection algorithm for scar bearing is proposed. The first step is to perform vertex management on the 3D reconstructed scar bearing model through the quad-tree; the second step is to select the appropriate algorithm for the calculation of the maximum interference distance by considering bearing shape and its motion characteristics. The research shows that the algorithm can quickly and efficiently test the dynamic interference and calculate the interference distance for the bearing with scar, which can effectively improve the efficiency of bearing …


Adaptive Backstepping Control Based Closed-Loop I/F Control Of Sensorless Permanent Magnet Synchronous Generator, Chang Da, Yu Yang, Zengqiang Mi, Xiaoming Zheng, Chenjun Sun Nov 2019

Adaptive Backstepping Control Based Closed-Loop I/F Control Of Sensorless Permanent Magnet Synchronous Generator, Chang Da, Yu Yang, Zengqiang Mi, Xiaoming Zheng, Chenjun Sun

Journal of System Simulation

Abstract: A novel strategy applied closed-loop adaptive back-stepping control to permanent magnet synchronous generator (PMSG) is proposed targeting the problem of the modification of torque for mechanical elastic energy storage (MEES) system utilizing PSMG as power source. This paper establishes the mathematical model of MEES system and PMSG, and presents the closed-loop adaptive backstepping control which makes the angle between the dq axis oriented by the current of stator and the dq axis oriented by the rotor a constant value via the speed and current closed-loop based on the analysis of open-loop I/f control. The closed-loop adaptive back-stepping control can …


Multi-Projector Annular Display Based On Laser Marking Points, Shuiying Ge, Jitao Neng, Shibiao Xu, Xiaopeng Zhang Nov 2019

Multi-Projector Annular Display Based On Laser Marking Points, Shuiying Ge, Jitao Neng, Shibiao Xu, Xiaopeng Zhang

Journal of System Simulation

Abstract: This paper proposes a software method to construct a multi-projector display system. Based on the known geometric parameters of the projection curve surface such as radius, radian and the height of the circular-screen and the laser marking points, this method calculates the projection matrix of each projector to warp the image of each projector correctly. The Alpha blending and gamma rectification techniques are used to do the color blending. The experimental results show that the geometric warping and color blending effects of the seamless multi-projector display system are stable and effective.


Future Traffic Accident Risk Investigation Based On Human-Machine-Environment Factors, Yuan Quan, Gao Yan, Chenlu Qiu Nov 2019

Future Traffic Accident Risk Investigation Based On Human-Machine-Environment Factors, Yuan Quan, Gao Yan, Chenlu Qiu

Journal of System Simulation

Abstract: Based on the theory of human-machine-environment system engineering, this paper investigated the developing trends of autonomous vehicles and the types of traffic crashes in China, and integrated changing human-vehicle-road factors of traffic system to speculate the possible new types and scenarios of traffic crashes. The recent occurred crash cases involving autonomous vehicles were concerned and investigated. In future, some new affecting factors such as the mix traffic with various autonomous vehicles and piloted vehicles, the switching of driving behavior between human and machine, and the information security of intelligent traffic system, may cause traffic crashes. Among these, the human …


Potential Users Of Battery Electric Vehicle Based On Big Data Of Floating Vehicles, Kong Yuan, Yiman Du, Jianping Wu, Kezhen Hu Nov 2019

Potential Users Of Battery Electric Vehicle Based On Big Data Of Floating Vehicles, Kong Yuan, Yiman Du, Jianping Wu, Kezhen Hu

Journal of System Simulation

Abstract: Nowadays, the Chinese government is strongly pushing the adoption of new energy vehicles, so it is of great significance to find the most suitable users of EV (Electric Vehicle). This paper did a data mining work to find out target user group of EV based on two-month traveling data, driver information and vehicle attribute information of 12,000 floating vehicles in Beijing. The results show that residential area is more suitable to push the adoption of EV than other functional areas; adding charging piles in the destination area can turn the 9.2% of drivers who are not suitable for EV …


Novel Star Map Identification Algorithm Using Improved Radial Features, Junyang Zhao, Zhili Zhang, Dianjian Liu, Zhaofa Zhou, Zhenjun Chang Nov 2019

Novel Star Map Identification Algorithm Using Improved Radial Features, Junyang Zhao, Zhili Zhang, Dianjian Liu, Zhaofa Zhou, Zhenjun Chang

Journal of System Simulation

Abstract: In order to improve the star map identification efficiency and insure the identification veracity, the radial feature is ameliorated by cyclic feature, and a new star map identification method based on the ameliorative radial feature matching is proposed. The star map data are processed according to quadrant order to establish the database of new radial feature. The radial feature matching between the observation stars in the matching star map and the reference star in the feature database is carried out in the order of circumferential quadrant. The star with the largest count in the star database is the final …


Simulation Analyses Of A Method For Extracting Dynamic Parameters From Forced Vibration Responses, Yumiao Wei, Zhili Zhang, Zhengjun Chang, Junyang Zhao, Xiangyang Li Nov 2019

Simulation Analyses Of A Method For Extracting Dynamic Parameters From Forced Vibration Responses, Yumiao Wei, Zhili Zhang, Zhengjun Chang, Junyang Zhao, Xiangyang Li

Journal of System Simulation

Abstract: To characterize the dynamic features of electromechanical system, a method is researched for dynamic parameters extraction from the forced vibration responses. The forced vibration response signals are processed by HVD method, and the free damped oscillation components are acquired. The SSA-FREEVIB analysis is conducted for the obtained components to measure the dynamic characteristics. The equalization procedures are implemented for the backbones and damping data, the resonance frequency and Q value are therefore accurately estimated. Simulation results show that the calculated resonance frequency and Q value coincide well with the theoretical values. A good anti-noise performance of the proposed …


Study On The Matching Mediation Method Between Virtual Maintenance Personnel And Work Steps, Yunrong Zhang, Zhili Zhang, Xiangyang Li, Weichang Xu, Kuixia Han, Li Liang Nov 2019

Study On The Matching Mediation Method Between Virtual Maintenance Personnel And Work Steps, Yunrong Zhang, Zhili Zhang, Xiangyang Li, Weichang Xu, Kuixia Han, Li Liang

Journal of System Simulation

Abstract: Aiming at the problem that each maintenance worker cannot play a full role in dealing with the concurrent conflict of maintenance steps, this paper puts forward a matching mechanism between maintenance steps and maintenance workers according to the level of authority, expounds the status information of maintenance workers, divides the difficulty level of maintenance steps, and gives the matching process between maintenance workers and maintenance steps. The matching process is modeled and simulated by using colored Petri nets and CPN tools. The simulation results show that the matching mechanism can solve the problem that the role of …


Application Of Constraint Force Equation Methodology In Aircraft Stage Separation Dynamics Simulation, Yongji Wang, Bangbang Li, Liu Lei Nov 2019

Application Of Constraint Force Equation Methodology In Aircraft Stage Separation Dynamics Simulation, Yongji Wang, Bangbang Li, Liu Lei

Journal of System Simulation

Abstract: The separation process of two-stage aircraft can be divided into three periods: lock-up period, constraint period and detachment period. The guide pins have constraint on two stages, which permit only translation in X-axis direction. To avoid the complex force analysis, the guide pins can be regarded as a joint of one degree of freedom. By adding the constraint and freedom equations to traditional separation dynamics equations, a dynamics model based on constraint force equation (CFE) methodology was built. The constraint force and moment can be obtained by solving constraint force equations. The constraint force equation (CFE) methodology was …


Ground Coverage Stitching Simulation Algorithm For Remote Sensing Satellite, Shuhao Liu, Wang Tong, Zhang Yue Nov 2019

Ground Coverage Stitching Simulation Algorithm For Remote Sensing Satellite, Shuhao Liu, Wang Tong, Zhang Yue

Journal of System Simulation

Abstract: Ground coverage stitching is the base of remote sensing satellite mission simulation. A coverage stitching simulation algorithm is proposed, considering big time step and attitude maneuver simulation. Transient coverage region is computed by light of view intersection and tangent searching methods. Transient coverage boundaries of different simulation times are stitched by two-dimension convex hull algorithm. Between points of the stitched region polygon edges, new vertexes are interpolated. With the method proposed, limb coverage problem and coverage fusion when time step is large can be solved. Computer simulation results show that the algorithm achieves a fine accuracy and …


Two-Machine Co-Simulation Based On Mobile Augmented Reality, Zhili Zhang, Wang Chao, Long Yong, Shaodi Wang Nov 2019

Two-Machine Co-Simulation Based On Mobile Augmented Reality, Zhili Zhang, Wang Chao, Long Yong, Shaodi Wang

Journal of System Simulation

Abstract: Aiming at the problems that virtual training system was not convenient and was only performed in a single operation at present, a dual-machine collaborative system based on mobile augmented reality was designed. A portable augmented reality system was developed on the Unity3D platform with Tango technology. The photon server and LAN architecture were built on the basis. The client was built on the mobile platform of Lenovo PHAB2 Pro, and the co-simulation on dual-machine was implemented. Resultof the simulation proved the feasibility of combining augmented reality with photon server, and provided a set of practical development solutions for …


Facial Expression Synthesis Using Mals-Based Bilinear Factorization Model, Jiaci Guo, Shuling Dai Nov 2019

Facial Expression Synthesis Using Mals-Based Bilinear Factorization Model, Jiaci Guo, Shuling Dai

Journal of System Simulation

Abstract: Study on the facial expression synthesis is a constructive and creative subject in the field of virtual reality technology. The bilinear model is used for facial expression synthesis by separating the identity factor and the expression factor. The translation procedure in the bilinear model always requires a repetitive computation of matrix inverse operations to reach the identity factor and the expression factor. This computation may be instable when the observation data has the correlation or noisy information. In order to increase the stability of the bilinear model for expression synthesis, the modified iterative least square (MALS) regression is introduced …


Temporal Network And Its Application, Mingzhi Zhang, Luo Kai, Wu Xi, Qingjun Zhang Nov 2019

Temporal Network And Its Application, Mingzhi Zhang, Luo Kai, Wu Xi, Qingjun Zhang

Journal of System Simulation

Abstract: The traditional method which aggregates the information in a period of time to the static network cannot reflect effectively the dynamic features between the network nodes and their relations. The temporal network and its applications were studied. The temporal network was introduced and the differences between temporal network and static network were analyzed. The types and the two kinds of representation methods of temporal network were divided. The model of temporal network was constructed. Temporal path and temporal distance were discussed. Taking the vulnerability analysis of space information network for example, the results show the advantages of temporal network …


Numerical Simulation For Airflow Field Around Car Wheels, Haibo Huang, Xudong Yu, Qingguo Liu, Zhang Tao, Jianan Dong Nov 2019

Numerical Simulation For Airflow Field Around Car Wheels, Haibo Huang, Xudong Yu, Qingguo Liu, Zhang Tao, Jianan Dong

Journal of System Simulation

Abstract: The airflow field characteristics around the wheels have great influence on the flying of road dust and tire wear particles. Using the rotating wall boundary technology, an aerodynamic model of the vehicle-tire was built and verified. The airflow field around the wheels was obtained. The results show that the two airflows between the wheel and the wheel guard meet leading to the vortex. The airflows mainly overflow near the intersection. Due to the significant pumping effects, the airflow tends to fly to outside and upward near the front and rear wheels, respectively. In the …


Effect Of Flow Field Environment On Microstructure Surface Preventing Microorganism Attachment, Chunxi Li, Quanxi Xue, Xiangshan Zhang, Xuemin Ye Nov 2019

Effect Of Flow Field Environment On Microstructure Surface Preventing Microorganism Attachment, Chunxi Li, Quanxi Xue, Xiangshan Zhang, Xuemin Ye

Journal of System Simulation

Abstract: The kinetic characteristics of microorganism model moving in different surfaces and flow field environments are simulated. The internal flow dynamics and the inherent mechanism of antifouling on microstructure surface are examined. The results indicate that for the static flow field, vortices are generated in the micro-pits as microorganism moves above microstructure surface. The velocity in the microstructure surface is greater than that in the smooth surface, and the strain rate and shear stress exerted on microorganism are relatively smaller resulting in the rapid passing the microstructure surface. For the dynamic flow field, the flow field presents regular fluctuations …


Parameter Optimization Analysis For Double Reheat Units Based On Particle Swarm Optimization, Wenfeng Fu, Haiwen Chen, Lanjing Wang Nov 2019

Parameter Optimization Analysis For Double Reheat Units Based On Particle Swarm Optimization, Wenfeng Fu, Haiwen Chen, Lanjing Wang

Journal of System Simulation

Abstract: The thermodynamic system parameter optimization was established for double reheat ultra-supercritical units. Taking a 660MW unit as an example, some vital parameters including feedwater enthalpy rise distribution, feedwater temperature, reheat steam pressure, number of feedwater heaters and main steam parameter were analyzed based on particle swarm optimization. The result shows the unit thermal efficiency can be further improved by optimizing apparatus interface parameters. The second reheat pressure has more influence on the unit thermal efficiency than the first reheat pressure. When adding the number of feedwater heaters, low pressure heater is a better choice for improving unit thermal efficiency. …


Recognition Method On Two-Phase Flow Regime Based On Cross Recursive Analysis, Yongbo He, Yushan Dong, Rongrong Xue Nov 2019

Recognition Method On Two-Phase Flow Regime Based On Cross Recursive Analysis, Yongbo He, Yushan Dong, Rongrong Xue

Journal of System Simulation

Abstract: Aiming at the problems that the two-phase flow regime recognition speed is slow and the recognition accuracy is low, a flow regime recognition method is proposed based on cross recursive analysis (CRA) without imaging. The false nearest neighbors are used to analyze flow regime capacitance values measured by capacitance sensor to obtain an optimal embedding dimension; and the embedding dimension of cross recursive plot is established for several typical flow patterns. The capacitance values of the simulation flow regimes and the reference flow regimes are analyzed using cross recursion to get a set of cross recursive plots. The similarity …


Error Control On Unequal Diameter Machining Of Arc Surface Cam, Hu Dongfang, Jianwei Guo Nov 2019

Error Control On Unequal Diameter Machining Of Arc Surface Cam, Hu Dongfang, Jianwei Guo

Journal of System Simulation

Abstract: The effective control for the machining error is an important means for obtaining high precision and high efficiency of the unequal diameter profile machining of the arc surface cam. According to the space meshing principle and the rotation transformation tensor method, the contact line between the tool and the cam is analyzed; the cutter position offset and direction in the machining process are calculated. The actual working profile of the unequal diameter machining cam equation is established. Calculation method of normal error of globoid cam profile is deduced by the principle of differential geometry. The comparison between the …


Design Method Of Tactical Level Hexagonal Wargame Map, Fen Tang, Zhang Xin, You Xiong, Zhiqiang Wu, Kunwei Li Nov 2019

Design Method Of Tactical Level Hexagonal Wargame Map, Fen Tang, Zhang Xin, You Xiong, Zhiqiang Wu, Kunwei Li

Journal of System Simulation

Abstract: Wargame map is an indispensable component of wargame. The current research on wargame map focused itself on the hexagonal grid segmentation, the terrain quantization models and relevant algorithms, and the technical realization of the application algorithm based on wargame map. However, the wargame map design is inadequate in corresponding instructions and methods. Therefore, based on the traditional map design method and fully taking into account the characteristics of the army tactical level hexagonal wargame map, the principle and process of army tactical level hexagonal wargame map design are proposed, and the critical steps in the process of the wargame …


Optimization For Unrelated Parallel Machine Scheduling With Deteriorating Jobs, Xuan Hua, Yingying Qin, Xueyuan Wang, Bailin Zhang Nov 2019

Optimization For Unrelated Parallel Machine Scheduling With Deteriorating Jobs, Xuan Hua, Yingying Qin, Xueyuan Wang, Bailin Zhang

Journal of System Simulation

Abstract: Unrelated parallel machine scheduling problem with deteriorating jobs is studied with the objective of minimizing the maximum completion time. The processing time of a job varies with its beginning time which is denoted as an increasing function of its starting time. It is assumed that each job has its own different deterioration rate on each machine. A mathematical programming model is formulated for the NP-hard problem. An improved genetic algorithm based on two segment coding and self-adaptive adjustment of genetic parameters is then designed to make job scheduling and machine allocation more reasonable. Through the simulation experiments of different …


Optimum Design For Crankshaft Of Mud Pump Based On Response Surface Model, Liu Jun, Zhang Hong, Huang Hua, Chang Ping Nov 2019

Optimum Design For Crankshaft Of Mud Pump Based On Response Surface Model, Liu Jun, Zhang Hong, Huang Hua, Chang Ping

Journal of System Simulation

Abstract: The mud pump is the heart of an oil rig, and the crankshaft is one of the key components of the mud pump. To achieve the lightweight structural design of the mud pump, it is very important to optimize the structure of the crankshaft. The model is simplified and the structure is analyzed theoretically. The optimization module is used to optimize the parameters;and the response surface model is established. The multi-objective genetic algorithm is used to optimize the design; and the scheme of slotting on the crankshaft flange is put forward according to the production process. Through the simulation …


Adaptively Resampling 3d Mesh Models Based On Editable Features, Jiajia Dai, Lipeng Fan, Mingyong Pang Nov 2019

Adaptively Resampling 3d Mesh Models Based On Editable Features, Jiajia Dai, Lipeng Fan, Mingyong Pang

Journal of System Simulation

Abstract: We propose a hybrid algorithm for adaptively resampling 3D triangulations by user-defined editable features. The method parameterizes a 3D mesh model into 2D parameter plane, and the geometric properties of the original model is calculated and represented on a planar domain. According to a constructed geometric image of the original model and user-defined editing information, the method creates a global density function for the resampled model. The sampling density function is employed to control distribution of samples in the 2D parameter domain. The method uses centroidal Voronoi tessellation technique to further optimize local distribution of the sampled points. The …


Design And Implementation Of Asd Children’S Cognitive Education System Based On Unity3d, Xuejing Gu, Kaifeng Zhang, Yucheng Guo, Zhiliang Wang Nov 2019

Design And Implementation Of Asd Children’S Cognitive Education System Based On Unity3d, Xuejing Gu, Kaifeng Zhang, Yucheng Guo, Zhiliang Wang

Journal of System Simulation

Abstract: ASD (autism spectrum disorder) is a broad sense of autism. In order to improve cognitive deficits of children with ASD, promote cognitive generalization in ASD children, an education system was designed using Unity3D. The built-in physical engine of Unity3D was used to create a game environment which conformed to the physical laws of the real world by simulating the effects of gravity, buoyancy and collision. The Agent technology and state machine were used to realize the representation and control of virtual scene. Camera and face detection technology were used to realize facial imitative cognitive training. The preliminary test showed …


Remote Real-Time Rendering System Based On Graphics Cluster, Haiyang Liu, Xiaofeng Hu, Lei Xu Nov 2019

Remote Real-Time Rendering System Based On Graphics Cluster, Haiyang Liu, Xiaofeng Hu, Lei Xu

Journal of System Simulation

Abstract: In order to solve the problems of rendering application for many remote users with different requirements, according to the multi-user oriented asynchronous distributed application mode in graphics cluster environment, a general framework of remote real-time rendering system based on graphics cluster is proposed, and the main functional modules are designed. The integrated application of key technologies, including GPU rendering based on Docker, dynamic load balancing and real-time transmission control of images, is analyzed. The effectiveness of system solution is demonstrated by concrete examples.


A New Memristor Chaotic System And Its Application In Image Encryption, Shuanghui Qu, Zhihong Yang, Xuwei Rong, Shuhua Wu Nov 2019

A New Memristor Chaotic System And Its Application In Image Encryption, Shuanghui Qu, Zhihong Yang, Xuwei Rong, Shuhua Wu

Journal of System Simulation

Abstract: A new memristor chaotic system is designed by the method of bringing an ion migration memristor into the Chen system equation. The basic dynamic characteristics of the memristive system are investigated via bifurcation, Lyapunov exponent et al, which proves the validity of the new system. The new memristor system is applied in the image encryption to improve the security of the encryption key. A dual encryption algorithm is used, which makes every pixel value of plaintext influence all pixel values of ciphertext. Although there is no direct link between plaintext and ciphertext, the sensibility of ciphertext varying with …


Lpv Controller Design Of Wind Turbine With Maximum Power Point Tracking, Zheng Yang, Dinghui Wu, Zhicheng Ji Nov 2019

Lpv Controller Design Of Wind Turbine With Maximum Power Point Tracking, Zheng Yang, Dinghui Wu, Zhicheng Ji

Journal of System Simulation

Abstract: A design method of the polytopic controller under the maximum power point tracking (MPPT) is proposed in addressing the low efficiency of the wind turbine under rated wind speed and uncertainty of the wind speed. Considering high nonlinearity of the aerodynamic system, the Jacobi linearization and the convex decomposition technique are employed to transform the wind turbine system into a polytopic linear parameter varying (LPV) model with the bias torque of the aerodynamic torque as the scheduling variable. By solving the linear matrix inequalities (LMIs), a polytopic LPV controller is obtained. The simulation results show that the designed controller …


Spatial Spectrum Estimation Method Of Flank Twin-Line Array Based On Cross-Spectrum Correlation, Zhizhong Li, Wang Sen, Zhongliang Xu, Weiguo Dai, Qijun Liu Nov 2019

Spatial Spectrum Estimation Method Of Flank Twin-Line Array Based On Cross-Spectrum Correlation, Zhizhong Li, Wang Sen, Zhongliang Xu, Weiguo Dai, Qijun Liu

Journal of System Simulation

Abstract: Considering the structural features of the flank twin-line array, researches on spatial spectrum estimation of twin-line array based on adaptive beam-forming and cross-spectrum correlation were carried out. A spatial spectrum estimation method based on cross-spectrum correlation is proposed according to the theory of cross-spectrum. The study of spectrum estimation performance comparison of the twin-line array was finished by that method combined with the conventional beam-forming and the adaptive beam-forming respectively. The results prove that the method based on cross-spectrum correlation has a better capability in noise suppression; and the method, which combined adaptive beam-forming with cross-spectrum correlation, is the …